SU Qiang, LI Cheng-yu, WANG Jing, LI Juan, ZHANG Yan-li, GUO Chong-feng, LU Yu-hua. Electron Trapping Materials Doped with Rare Earth Ions[J]. Chinese Journal of Luminescence, 2005,26(2): 143-148
SU Qiang, LI Cheng-yu, WANG Jing, LI Juan, ZHANG Yan-li, GUO Chong-feng, LU Yu-hua. Electron Trapping Materials Doped with Rare Earth Ions[J]. Chinese Journal of Luminescence, 2005,26(2): 143-148DOI:
Defects can be produced in the matrix by aliovalent ionic substitution or by high-energy radiation. Electrons or holes can be trapped by these defects. Light will emit by radiative recombination of these electrons and holes released from traps with different depth. Some important luminescence materials doped with rare earth ion Eu
2+
or Mn
2+
such as long-lasting phosphorescence and solid dosimeters are based on this electron trapping process. Recently
we synthesized some electron trapping materials for long-lasting phosphors use. We prepared some glasses possessed of long-persistent phosphorescence and information storage properties. For example
ZnO-SiO
2
-B
2
O
3
:Mn
2+
glass shows red long afterglow. It is interesting to note that photo-stimulate long-persistent phosphorescence phenomenon is observed
information can be written and storages in the glass with 254nm UV light and read out by visible or IR light. Depending on different annealing temperatures
this glass can transform into glass ceramics emitting yellow or green long-lasting phosphorescence light. We synthesized also the yellow phosphor CaGa
2
S
4
:Eu
2+
Ho
3+
and red phosphor CaS:Eu
2+
Tm
3+
with long-persistent phosphorescence properties. For improving the stability of the latter phosphor
we studied the oxide coating. We studied also the solid dosimetric property of some borates doped with Dy
3+
or Tb
3+
such as Sr
0.93
Dy
0.07
B
4
O
7
or Zn
0.96
(BO
2
)
2
:0.04Tb. After aliovalent ionic substitution and β-ray or γ-ray radiation
defects and traps are formed. The respond of the thermoluminescence intensity with the dose is linear